Ammunition for small arms



Jam 1942- c. M. O'NEIL 2,269,316

AMMUNITION FOR SMALL ARMS Filed July 5, 1938 II-III...-

' 191/ yen/tor m 77% aw A liar/gays Patented Jan. 6, 1942 UNITED STATES PATENT OFFICE AMMUNITION FOR SMALL ARMS Charles M. ONeil, Hopkins, Minn.

Application July 5, 1938, Serial No. 217,378

3 Claims.

This invention relates to ammunition for small arms, particularly to cartridges utilizing the modern nitrocellulous powders having fast ignition properties.

The new high power powders such as the socalled smokeless powder have done much to increase the velocity and range of ammunition. The explosive force of such powders, however, is so great that in the conventional construction now utilized, manufacturers find it necessary to leave some air space in the powder chamber of the cartridge for cushioning purposes to prevent disruption of the case when the cartridge is fired and also to speed up ignition.

In conventional cartridges used with high high power explosives the powder charge is ignited by the primer at the very rear end of the powder chamber and despite the rapid ignition of smokeless powder the rear ignited portion of the charge forces the forward portion of the powder against the projectile and into the bore of the rifle before it is completely burned. This action is accentuated in cartridges of the bottle neck case type, choking action of the powder taking place as it is forced into the restricted projectile receiving portion of the easing. The burning continues in the barrel of the fire arm, and consequently with rapid firing the barrel heats up badly and in many cases injures the bore and the rifling both from overheating and from the large amount of erosive deposited therein.

The above recited forcing of a part of the charge into the barrel further tends to build up unnecessary pressures in the rear portion of the cartridge case and againstthe bolt head or breach of the arm. It is the method of ignition just described which makes it unsafe to load conventional cartridges with a maximum charge pratically no burning of the powder takes place outside of the cartridge case in the barrel of the fire arm.

More specifically it is an object to provide a cartridge of the class described wherein the powder chamber is packed with high explosive powder and wherein a flash tube is used to convey the primer flash forward from the detonated primer to a central portion of the charge where it ignites the powder charge to its forward end. Such structure tends to force the projectile forward, not by the compressed forward portion of a rear ignited charge, but rather to produce a propelling force by the gas pressure itself. The results and function of such ignition with smokeless or high power powder is entirely different than with the old types of less explosive powders since ignition of the antiquated types of powder was comparatively slow, and regardless of where the first point of ignition of the powder takes place, gas pressure alone could not force the projectile into the bore, but always some considerable burning of the powder would necessarily take place within the barrel.

Still another object is the provision of a new and improved method in the ignition of high explosive powder in small arms ammunition.

With my improved cartridge construction practically the entire propellant charge is burned within the cartridge case and consequently the barrel is maintained at a relatively cool temperature and little erosive material is trans mitted thereto. Furthermore, the propellant effect of the ignited powder with my construction is progressive as distinguished from conof powder. Dangerous explosions would occur if 4 some air space were not left in the powder chamber.

It is an object of my invention to provide simple and inexpensive improvements in cartridge construction for small arms which will materially increase the velocity, range and propellant force of the ammunition and which will substantially eliminate the over-heating of the bore and barrel during rapid fire, thus increasing the life of the fire arm.

A further object of my invention is to enable a maximum charge of the most powerful type of powder to be utflized in the powder chamber with safety and to provide for exceedingly rapid ventional ammunition in that the initial ignition through the discharge of flame forwardly in the forward end of the charge first reacts upon the projectile, and as ignition rapidly spreads to the greater part of the charge at the sides of the flash tube and the rear portion of the powder chamber, greater liberation of gas takes place as is necessary since the projectile is moving forward, increasing the space of the chamber in which the gas is liberated. A furtheradvantage is gained in that the said initial ignition and liberation of gas rather than being applied directly against the rear uncushioned base of the casing, is applied against the projectile thereby permitting much higher pressures to be utilized without danger of rupturing the cartridge case.

With my construction a much larger high explosive charge is possible in any given size case,

ignition of that charge in such a manner that the e y i in subst nti y reater velocit es than possible with the loose charges now utilized at usable pressures.

It is another object of my invention to provide a new and improved method of igniting the explosive charge and propelling the projectile in small arms ammunition. v

These and other objects and advantages of the invention will more fully appear from the follow ing description made in connection with the accompanying drawing, wherein like reference characters refer to the same or similar parts throughout the several views,'and in which:

Fig. 1 is a section taken longitudinally through an embodiment of my inventon;

Fig. 2 is a view mostly in side elevation with some parts broken away showing a cartridge having a somewhat diiferent form of flash tube, and.

Fig. 3 is a detail view showing a still different form of flash tube integrally formed with a special primer.

Referring to the device illustrated in Fig. 1, a cartridge case C, for the most part of conventional construction, is shown having the diminished neck 5 which receives and holds the usual tube I i open at both ends extends axially from the flash end of the primer 7 to approximately the central portion of the powder chamber, and as shown in Fig. 1, has its outer end threaded for engagement with a thread on the bore of the casing base 8.

The only difference between the form of my cartridge shown in Fig. 2 is that the flash tube II has a flaring outer end H a which seats in a complementary formed recess in the bore of the casing. This head is securely held in place by the primer I which of course is forced into the primer recess in the usual manner when the cartridge is assembled.

In the structure illustrated in Fig. 3 a special combination primer and flash tube is shown, the

casing of the primer being integrally formed with the tube and the device being adapted for unitary insertion in loading the cartridge.

When my improved cartridge is fired the detonation of the primer causes a flash of fire to shoot out from the inner end of the flash tube H into the central portion of the powder charge. The initial ignition of the explosive thus takes place in approximately the axial as well as the longitudinal center of the charge and in a forward direction, the ignition of course spreading very rapidly from the central part of the charge to the base end of the powder chamber. Almost the entire charge forward of the flash tube is instantaneously ignited and the propulsion of the projectile thus is effected at the start mostly by gas produced rather than by the forward portion 0! the powder charge, as is the case with conventional high powered cartridges utilized at this time. It will further be seen that the effect of the explosion at the onset is not to apply the violence of the first exploded gas directly against the base of the shell and the breach lock, but the violence of this first explosive reaction is cushioned somewhat by the powder between the forwardly projected flash and the rear of the casing.

The lessening of the violence of the initial part of explosion with my structure has enabled me to completely fill or pack the powder chamber of conventional cartridge cases with powder of the most powerful type without danger of accident or rupture of the case when the explosion occurs. This positively cannot be accomplished with cartridges wherein the powder is ignited in the usual manner at the very rear of the powder chamber. Thus with standard sized cartridge cases I have been able to materially increase the. range and power of small arms ammunition.

It will further be noted that explosive power during firing is progressively applied through the ignition rearwardly of the greater part of the charge after the initial ignition of that portion of the charge directly behind the projectile.

Extensive use of my improved method and construction have shown that material increase in velocity and range is obtained. For example, numerous tests with thirty caliber conventional United States Army cartridges of the 1906 year type and of the conventional construction with a maximum loading of 46 grams of smokeless powder, producing an average velocity of 2400 feet per second. Utilizing the same conventional cartridge case with my structure and method 55 grams of powder can be utilized, the same being slightly compressed or packed into the chamber and with the same projectile (220 grain bullets) I have in continuous tests obtained a projectile velocity of 2700 feet per second, with safety and without producing friction from sticking of the shell after firing.

It will, of course, be understood that various changes may be made in the form, details, arrangement and proportions of the various parts without departing from the scope of my invenion.

What is claimed is:

1. A rifle cartridge comprising the usual casing having a base, an open end and a powder chamber formed therebetween, with a primer in said base, a flash tube extending from said primer to a point approximately in the medial portion of said chamber and open to the chamber at that point, a projectile mounted in said open end of the casing, and a charge ofgranular nitro-cellulose powder completely filling said chamber around and forwardly of said tube so that said charge is in substantially full surface contact with the rear end of the projectile.

2. A rifle cartridge comprising the usual casing having a base and an open forward end, a primer in said base, a projectile fitted into said open forchamber and surrounding said flash tube so as to occupy the entire available space between said base and the rear surface of said projectile.

3. The cartridge defined in claim 2, said charge of granular powder being under slight compression within the chamber, and said flash tube having its forward end open at a point approximately midway between the ends of said charge.

CHAS. M. ONEIL. 

